The efficacy of cannabidiol on renal angiomyolipoma and subependymal giant cell tumor volume in tuberous sclerosis complex

Abstract

In patients with tuberous sclerosis complex (TSC) the upregulation of the mechanistic target of rapamycin (mTOR) pathway leads to the development and growth of subependymal giant cell tumors (SGCTs) and renal angiomyolipomas (AMLs). Drugs that inhibit the mTOR pathway, such as sirolimus, can reduce the size of both SGCTs and AMLs. Recent preclinical studies have suggested cannabidiol (CBD) may mediate the mTOR pathway, however, its exact effects are unclear. This study examines the volumes of SGCTs and renal AMLs in patients with TSC during treatment with purified CBD for refractory epilepsy. We retrospectively reviewed the medical records of patients with TSC with radiological evidence of AMLs and SGCTs who were being treated with plant-derived highly purified CBD in oral solution (Epidiolex®, GW Research Ltd) for refractory epilepsy at Massachusetts General Hospital. Patients who had surgical intervention for AMLs or SGCTS, and patients who had been treated with mTOR inhibitors were excluded. The volumes of SGCTs and dominant renal AML were measured before and after CBD initiation using abdominal and brain scans and compared. Patient demographics and CBD doses were collected from medical records. Six out of the seven dominant renal AMLs and three out of the three SGCTs increased in volume during CBD treatment. One AML had a decrease in volume after CBD initiation which was not considered significant. The results suggest that unlike mTOR inhibitors, CBD treatment does not decrease the volume of SGCTs or AMLs in TSC patients.

Keywords: Cannabidiol; Epilepsy; Renal angiomyolipoma; Subependymal giant cell tumor; Tuberous sclerosis complex.